In order to connect a circuit element to its associated circuit, solder is usually used because it provides a good electrical and mechanical interconnection. In certain instances, however, it is desirable that solder not be used on the circuit element so as to minimize the effect of the connection on performance of the element and also to reduce the expense of making the connection.
Such factors are relevant to the manufacture of smoke detectors incorporating piezoelectric horns. In recent years piezoelectric material has become more and more widely used in transducers to convert electrical signals into sound and vice versa. Such a transducer may be used in a smoke detector which produces an alerting signal in the presence of smoke. Very basically, such as smoke detector includes smoke-sensing means and a piezoelectric horn, which horn, in turn, has an oscillator and a piezoelectric transducer. The piezoelectric transducer, excited by electrical signals from the oscillator, produces vibrations at a particular audio frequency which constitutes an alerting tone.
In currently available piezoelectric horns, the piezoelectric transducer is electrically connected to the oscillator circuit by means of wires soldered directly to the transducer. It has been found that these soldered connections have an undesirable effect on the efficiency of the transducer itself, i.e. its audio output for a given input. Also, a soldered connection is time consuming to make, thereby adding to the cost of manufacturing the transducer. Moreover, such soldering tends to vaporize the silver electrodes which are commonly used on piezoelectric transducers.